Psychosocial Interventions for Adult Survivors of Mass Casualty Events: A Systematic Review and Network Meta Analysis

Background: Adults exposed to mass casualty events (MCEs), including civilians, first responders, and medical personnel, experience elevated risk for PTSD and related depression and anxiety. Evidence on psychosocial interventions in disaster/humanitarian contexts is heterogeneous, and few syntheses evaluate and rank interventions across outcomes to guide social work and emergency response planning.

Objectives: This systematic review and network meta-analysis (NMA) aimed to (1) evaluate comparative effectiveness of psychosocial interventions for adults exposed to MCEs on PTSD, depression, and anxiety outcomes and (2) rank interventions to inform clinical and policy prioritization in disaster and humanitarian settings.

Methods: Following PICOS and PRISMA-NMA guidance, we synthesized studies of psychosocial interventions for adults (18+) with MCE exposure within five years prior to each study’s data collection. We included English- and Spanish-language sources from both peer-reviewed and unpublished literature. Eligible designs included randomized and non-randomized trials with ≥2 conditions and pretest/posttest symptom measurement for PTSD, depression, and/or anxiety. Study selection involved independent dual screening. Random-effects NMAs were conducted in R (v4.4.3) using the netmeta package with standardized mean differences (SMDs), DerSimonian-Laird τ², node-splitting for inconsistency, heterogeneity via I²/τ², and intervention rankings via P-scores. Potential publication bias was examined using Egger’s tests with funnel plots and trim-and-fill; sensitivity analyses excluded high-risk-of-bias studies.

Results: The search yielded 2,647 records; after removing 884 duplicates, 1,763 titles and abstracts were screened and 42 studies met inclusion criteria, comprising 7,904 participants across 23 countries. Most studies were RCTs (n=36), and 6 were non-RCTs. Interventions were grouped into 10 groups (e.g., cognitive behavioral therapy and integrative approaches, exposure-based interventions including Narrative Exposure Therapy, and early Eye Movement Desensitization and Reprocessing [EMDR]).

For PTSD, the largest effects versus inactive controls were observed for Testimony Therapy (SMD = 4.64; 95% CI [3.20-6.08]), early EMDR (SMD = 2.30; 95% CI [1.55-3.05]), exposure‑based interventions (SMD = 1.83; 95% CI [1.16-2.49]), and mind–body practices (SMD = 2.08; 95% CI [0.92-3.24]). For depression, Testimony Therapy demonstrated the largest effect (SMD = 4.26; 95% CI [1.75-6.78]), followed by Problem Management Plus (PM+; SMD = 2.47; 95% CI [0.58-4.36]). For anxiety, no intervention was superior to inactive controls. However, compared with active controls, PM+ showed a significant effect (SMD = 4.69, 95% CI [2.19-7.18]).

Conclusions/Implications: These findings support prioritizing Testimony Therapy and early EMDR to strengthen PTSD-focused response capacity in disaster and humanitarian social work practice. Results also highlight Testimony Therapy and PM+ as effective approaches for depression and anxiety, with relevance for low resource, task shared delivery in rapid deployment and emergency response contexts. Limitations include risk of bias concerns in many RCTs, sensitivity of some PTSD rankings to study quality, limited availability of follow up data, and indications of potential publication bias across several outcome networks.